Interesting bug in FBX import

Unity Engine
,
1

Hi,

I just noticed a VERY weird issue with the FBX import today on U3 beta 6.

I have two identical meshes that I import using “none” as normal/tangent generation options.

The other of the meshes has smoothing angle setting of 180 and the other has smoothing angle of 60.

Now, the weird thing: even though normal generation is disabled (and the smoothing angle setting is not adjustable, and should have zero effect on the generated mesh), the mesh with smoothing angle setting 60 generates roughly 1.5x more vertices when rendering.

Ie, in my scene, using mesh 1 results in 4k polygons and 4k vertices, using mesh 2 results in 4k polygons and 6k vertices.

Has anyone else noticed the same? Sounds like a bug to me?

br,
Sami

2

Why?

Do they vary in terms of UVs or vertex colors?

3

Yes Uvs or Hard&smooth edges subject is already know from most of the Unity’s users.

Here is a test I done months ago with a cube changing edges normal and Uvs checking the vertex count

4

Yeah, the UV’s are different (moved with an offset by the artist, but identical otherwise), but the meshes are basically the same.

Anyway, the problem is that the smoothing angle setting affects the number of the polygons even if the normal generation is turned off (= looks like a bug to me).

br,
Sami

5

Yes, I know that, but that wasn’t the point - the problem is that a disabled option has an effect on the output polygon count, which is something that should not happen.

br,
Sami

6

Which is why you should report a bug through the corresponding feature instead of posting here about it which is of no use :slight_smile:

7

Did that already - I was just asking if anyone else had noticed this, or was it just me messing up somehthing :stuck_out_tongue:

br,
Sami

8

seems that this bug is not corrected…

Or it was not a bug…

Can someone shed some light on this ?